The basic concept of specific surface area
in physical adsorption, the interaction between adsorbed molecules and surface molecules is intermolecular force, that is, van der Waals force. Physical adsorption can quickly reach equilibrium and is reversible. China will complete the construction of 1billion square meters of new green buildings. By reducing the pressure, the adsorbate can be desorbed
the adsorption heat of physical adsorption is close to the enthalpy change of gas-phase material condensation, similar to the condensation of gas on the solid surface. Physical adsorption often occurs at low temperature, which is monolayer or multilayer adsorption
in chemical adsorption, adsorbed molecules are combined with surface molecules by chemical bond force, including electron transfer, atom rearrangement, and the generation and destruction of chemical bonds. Therefore, chemical adsorption is similar to chemical reaction. The heat of adsorption is close to the enthalpy change of chemical reaction. I hope it can be helpful for you. It has high selectivity and is monolayer adsorption. The rate of chemisorption depends on the activation energy of chemisorption reaction, so the adsorption rate is often faster at high temperature. Chemical adsorption is difficult to desorb, and desorption may be accompanied by chemical changes
[comparison of characteristics of physical adsorption and chemical adsorption]
when studying adsorption, for different purposes, a variable is often fixed in the three quantities of adsorption capacity, adsorption temperature and adsorption pressure. The relationship between the other two quantities is measured and expressed by a curve, which is called an adsorption curveThere are generally three kinds of adsorption curves:
adsorption. "The electric vehicle expert added:" the performance isotherm of the materials used around the battery describes the curve of the relationship between the adsorption amount and the adsorption pressure at isothermal conditions.
the adsorption isotherm describes the curve of the relationship between the adsorption amount and the adsorption temperature at isobaric conditions.
the adsorption isotherm describes the relationship between the adsorption amount and the adsorption temperature at isobaric conditions. When the adsorption isotherm describes the adsorption amount, the adsorption static experimental machine mainly includes the curve of the relationship between the temperature and the adsorbate pressure
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